Method of and apparatus for drying china or other clay, fullers&#39; earth, pigments, whiting, and the like.



W. J. GEE.

METHOD OF AND APPARATUS FOR DRYING CHINA OR OTHER CLAY. FULLERS' EARTH, PIGMENTS,

Wl-HTING, AND THE LIKE.

APPLICATION HLED APR. 6, 1915.

Patented J uly 30, 1918.

2 $HEETSSHEET 3.

or other non-oxidizing or hari'nlessly oxidiz ing metal passing over grooved pulleys p and Q which are he )t under sufficient tension by means of suitab e tensioning devices such as springs r fixed at one end to the frame 8 of the machine and at the other end to levers t )ivoted at their upper ends in the frame. hose tensioning devices are in di' rect Contact with the wires and will therefore clean the wires before passing onto the table, and prevent touring the sheet of clay by means of small thereto. Each wire is provided with a separate tensionin device. The wires slide over the table 0 w ich is heated from below by any suitable means for instance by electric heaters u. The table'is composed of a mum her of transverse members y made of ordinary channel iron covered with sheet eluniinium. These members are placed close t g ther and form a practically nnintcr rupted fiat SUI-face which is very little liable to buckle under the inilucmu o. heat. Over practically the whole table e extend? n hood or which is divided by a ,ertition into two chambers. The upper ciamber communicates throu h pipes a with the suction ports of a centri ugal fan. 1, the discharge ends of which communicate through a spreader 2 with the rightend of the lower chamber. The hopper o is incased in e jacket a, the lower end of which jacket is in communication with the outlet end of the lower chamber, the arrangement being such that the clay within the hopper a is preheated by the waste heat from the hood. If desired the jacket may be incased with insulation as indicated at a.

The operation of the machine is as fol-- lowsr The rhino-clay is delivered by the expressing device from the hopper e on to l the endless band I) in the form of a llllll sheet, film or blanked This sheet, film or blanket sags between the longitudinal wires 1) and is supported mainly by the table (1. The longitudinal wires 5 however slide the film over the heated table 01. \Vliiiill it l'lliltlly dried to the desired degree and from which it is dis charged in the formot' flakes. In ordertoutilizc theheat as much as possible. air is drawn through the upper chamber of the hood 11:. This chamber is heated by the :ucmn arising: from the drying of the nmtrnul and also by radiated heat. The bruit-d air thus obtained is then forced through the lower chamber over the material to be dried and is thereafter utilized logclhrr w th the steam evaporated. by the drying process. for pro heating the lliill-(l'lill to be dried in any do sired lllttlll'lUl'tIl'lWlHtllt'ltlltl in Fig. 1. When drying china clay, it is advisable to preheat the material in the hopper almost i b iling point and to heat the table to a temperature of WNW- hit)" The heat, being! produced and utilized in comparatively small and articles of clay adheringconfined spaces, there is no difliculty in reducing the heat losses by efl'ective heat insulation obtained by lagging.

Although temperatures exceeding 300 C. would burn chine-clay, in this a paretus there is no danger of burning as t ie speed of the band can be adjusted to remove the clay from the table with a water content of about 125% which is the state in which china-clay is normally sold.

The particular construction of the endless band in the form of parallel wires has, inter alia, the advantage that the material to be dried is allowed to come more or less into contact with the heating table between two adjacent wires so that a direct heat trans mission is obtained in addition to the transmission by radiation. The wires constituting the endless band serve not only as means for moving the material over the table and transmitting the heat of the table to the material but they serve also as means for the egress of the steam produced by the drying of the clay. This steam trin'els along the wires until it reaches a crack in the sheet of clay through which it passes into the lbwer chamber of the hood. In this manner the formation of blisters is avoided, which might be caused by the shutting in of steam between the drying surface and the material to be dried and would have a very unfavorable effect on the elliciency of the a parntus.

It will be understood that if the invention is to be applied to material other than chinoclay the temperature employed will have to be altered according to the nature of the material to be treated, the choice of the temperatures being governed on the one hand by the desire to dry the material as rapidly 'as possible and on the other hand by the necessity of avoiding burning or otherwise spoiling the material.

I claim: I

1. The method of drying china clay, ful lers" earth, pigments, whiting, and nuuerial of like character, comprising the steps of continuously sliding the material in a thin sheet in plastic form through a heating de vice over a heated surface and in contact therewith to evaporate the moisture therefrom. substantially as described.

2. The method of drying, china clay, fu1- lcrs earth, pigments, whiting, and material of like clnuriu-tcr, comprising the steps of feeding material in a thin sheet and in plusti'e form onto a heated surface and sliding said sheet over said surface, and passing a current of heated air over said sheet during its passage ovor tho heated surface to carry off the moisture, substantially as described.

ii. The method of drying china clay, fullcrs earth, and material of a like character, comprising. the stops of continuously sliding the material in a thin sheet and in plastic form through a heating device and over a heated surface, and in contact therewith to evaporate the moisture therefrom and also forming conduits in the bottom of the sheet of clay during its passage through the drier to permit the generated steam to pass 05 therethrough, substantially as described.

4. An apparatus for drying material, comprising a movable eonveyer formed of a plurality of endless hands, a flat heating surface over which said hands are moved, and forming a support therefor. the space of the heating'surface between the wires also forming a support for the material to be dried, means for moving said bands, means for heating said surface, and means for feeding a. film of plastic material on the top of said hands to be carried over the heated surface thereby, substantially as described.

5. A drier, comprising a heated surface, means for heating said surface, a conveyer formed of a plurality of endless bands out of contact with each other arranged to move over said heated surface, means for moving said hands, a hood for said heated surface having a chamber therein arranged to be heated by the radiant heat from the heated surface, means for feeding a film of lastic material to be dried on said endless ands, said endless bends being arranged to move said film in a, continuous manner over the heated surface, there being an air inlet to said heated chamber in the hood, and means for passing said heated air over the film during its passage over the heated surface to carry off the moisture, substantially as described.

6. An apparatus for drying material, eomprising a movable eonveyer formed of a plurality of endless hands, a heating surface over which said bands are moved, and forming a support therefor, means for moving, said bands, means for maintaining each band under tension, means for heating said surface, and means for feeding a film of plastic material on the top of said bands to be carried over the heated surface thereby, substantially as described.

7. An apparatus for drying material, comthere being an air inlet to prising a movable eonveyer formed of a plurality of endless hands, a heating surface over which said bands are moved, and forming a support therefor, means for moving said bands, means for heating said surface, a hopper for the material to be dried, and an expressing device within said hopper for feeding the material in film form to said bands, substantially as described.

8. An apparatus for drying material comprising a conveyer formed of a plurality of endless hands, a heating surface over which said bands are moved and forming a support therefor, means for moving said band, means for feeding a film of plastic material on the top of said bands to be carried over the heated surface, and independent means for maintaining each band under tension and for cleaning 'said bands while passing the tensioning devices, substantially as described.

9. A drier comprising a heated surface, means for heating said surface, a, conveyer arranged to move over said heated surface, means for moving said conveyor, a hood for said heated surface having a chamber therein arranged to be heated by the radiant heat from the heated surface, a hopper havin means for feeding a film of plastic materiato be dried on said conveyor, said conveyor being arranged to move said m in a continuous manner over the heated surface,

said heated chamher in the hood, means for passing said heated air over the film during its passage over the heated surface to carry off the H1018- ture, and a jacket surrounding the hopper and arranged to receive the heated air and steam assing over the film to preheat the clay within the hopper, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

WILLIAM JOHN GEE. Witnesses:

HowAnn C. ELLIOII, O. J. WORTH. 

